Propulsion system for aircraft



Dec. 25, 1962 N. c. PRICE PROPULSION SYSTEM FOR AIRCRAFT Original FiledOct. 10, 1955 4 Sheets-Sheet 1 INVENTOR. NATHAN 0. PRICE Agent Dec. 25,1962 c, mc 3,070,328

PROPULSION SYSTEM FOR AIRCRAFT Original Filed 001;. 10, 1955 4Sheets-Sheet 2 N N N a Agent Dec. 25, 1962 N. c. PRICE PROPULSION SYSTEMFOR AIRCRAFT Original Filed 001;. 1o, 1955 4 Sheets-Sheet 3 INVENTOR.NATHAN C. PRICE Agent Dec. 25; 1962 N. c. PRICE 3,070,328

PROPULSION SYSTEM FOR AIRCRAFT Original Filed Oct. 10, 1955 4Sheets-Sheet 4 INVENTOR. NATHAN 'C.'PR|cE Agent 3,ti70,328 PROPULSIGNSYSTEM FER AIRCRAFT Nathan C. Price, Mexico City, Mexico (424% KeltonAve., Westwood, Qalif.)

Original appiication (lot. 10, 1955, Ser. No. 539,606, now Patent No.2,953,900, dated Sept. 27, 196i). Divided and this application Feb. 12,1958, Ser. No. 717,292

7 Claims. (Cl. 244-23) This invention relates to vehicular propulsionand relates, more particularly, to a system or mechanism for thepropulsion and directional control of aircraft capable of operation orflight from and to small landing areas.

This is a division of my co-pending application Serial Number 539,606,filed October 10, 1955, and on which United States Letters Patent2,953,900, entitled Combined Open-Cycle Closed-Cycle Powerplant forAircraft, issued on September 27, 1960.

The present invention is concerned, generally, with the propulsion ofvehicles, either inhabited or uninhabited, by reactive propulsionengines and by means of which the vehicle may be caused to ascendvertically or at a steep take-off angle, fly or cruise horizontally athigh or relatively high translational velocities, and descend or landvertically or at a steep landing angle. During such maneuvers apredetermined amount of boundary layer control effect may be imposed onthe aerodynamic upper surface of the aircraft, which is included amongthe relationships of the invention.

An object of the invention is to provide a vehicle propulsive systemcharacterized bya tubular plenum chamber equipped at its aft end with adirectionally controllable nozzle for translational propulsion and withlaterally directed nozzles for discharging into a jet pump tube forvertical or substantially vertical ascent and descent of the craft.

It is another object to provide a propulsion system in which the plenumchamber handles a large mass flow of air and is capable of directing theair flow aft through a propulsion nozzle, or downwardly through avertical jet tube, or through both tube and nozzle concurrently. The airflows internally at an average velocity of approximately 200 ft. persecond and finally discharges from the propulsive nozzle at the aft endof the plenum chamber at a jetting velocity of, say, 1350 ft. per secondto produce a jet thrust of approximately 1200 lbs. at a weight flow of,say, 28 lbs. per second. It is to be understood that the values justrecited are merely typical of a given embodiment and are not intended tobe restrictive. For vertical take-E and for landing, and in other caseswhere vertical thrust is desired, the propulsive nozzle is closed andlateral jet pump nozzles are opened to a vertical jet tube to furnishample energy for vertical lift.

Another object is to provide an aircraft propulsion system andinstallation wherein the main powerplant unit is so arranged and relatedwith respect to the airframe and jet pump to substantially promoteoverall efficiency during vertical ascent and descent, to reduce thenoise level and to increase translational flight efficiency of thecraft. The plenum chamber casing is nested in a fore and aft depressionor channel in the upper surface of the craft to bridge the upwardlyfacing bell-mouth entrance of the jet pump tube, to have the air inletof the powerplant face forwardly and slightly upwardly with respect tothe fore and aft neutral axis of the aircraft and to have its propulsivenozzles at or beyond the aft extremity of the craft. The powerplantreceiving depression is shaped to direct the cone of noise of the airinlet of the powerplant upwardly and forwardly to reduce the appar-3,070,328 Patented Dec. 25, 1962 '1 ice ent sound level and thedepression smoothly merges with the bell-mouth of the jet pump tube toreduce the turning losses during induced airflow into the jet pump tube.The nested or partially submerged powerplant blends into the profile ofthe aircraft to lessen parasitical drag, is readily accessible forinspection and servicing, and is structurally isolated from the aircraftbody except for its essential mounts. The directionally controllablepropulsive nozzle being at or beyond the rear extremity of the craftprovides a large turning moment and may be related to the controlsurfaces of the aircraft to induce a desirable airflow across thesesurfaces. The plenum chamber tube has a plurality of jet pump nozzlesspouting downwardly into the jet pump tube to induce airflow into thistube for vertical thrust while at the same time creating or promoting areduced or negative pressure condition at the bell-mouth and adjacentregions of the channel or de pression receiving the powerplant, therebyaiding vertical propulsion of the aircraft.

Another object is to provide a propulsion system of this kind whereinthe valves controlling the jet pump nozzles and the main propulsivenozzle are conjointly controlled to readily change over from verticalthrust propulsion to horizontal or translational propulsion. Theinternal passage of the tubular directional control bulb of the mainpropulsive nozzle remains open at all times to discharge a reactive jetuseful for pitch and turn trimming control and the jet pump exit isprovided with valves also operable as vanes for bank control, etc.during vertical take-off and landing.

A further objective of the invention is to provide a system of boundarylayer air extraction, active during flight, to increase lifting suctionon the upper aerodynamic surface of the aircraft.

Other objectives and features of the invention will become apparent fromthe following detailed description of a typical preferred form andapplication of the invention illustrated in the accompanying [drawingswherein: 7

FIGURE 1 is a side elevation of an aircraft incorporating the presentinvention with portions broken away to better illustrate the powerplantinstallation;

FIGURE 2 is a front view of the craft;

FIGURE 3 is a top or plan view of the craft;

FIGURE 4 is a rear View of the aircraft;

FIGURE 5 is an enlarged longitudinal sectional view of the major portionof the powerplant means with certain elements appearing in sideelevation;

FIGURE 6 is an enlarged vertical sectional view of the forward portionof the powerplant means shown in FIG- URE 5;

FIGURE 7 is an enlarged longitudinal sectional view of the aft portionof the powerplant means, the broken lines showing the closed position ofthe nozzle bulb;

FIGURE 8 is a substantially vertical sectional view taken as indicatedby line 88 on FIGURE 6;

FIGURE 9 is a diagrammatic view of the control linkage system; and

FIGURE 10 is an enlarged fragmentary sectional view of the perforatedwalls of the jet pump tube.

The propulsion system of this invention is, of course, suitable for usefor incorporation of crafts of various types and configurations and theparticular application of the invention illustrated in the drawings isto be understood as exemplary rather than restrictive. The airframe orbody 14 of the craft illustrated may be described as discoid in shape,having its skin or outer surfaces generated by arcs symmetrical aboutthe horizontal axis. In plan view the margins of the fuselage or body 10curve inwardly and forwardly to a pointed forward end 11, and curveinwardly and aft toward a somewhat less pointed aft end. It will beobserved the discoid fuselage or body has a large planform area topossess substantial aerodynamic sustentation in level flight and,therefore, the craft requires wings 12 of only limited dimensions ifwings are, in fact, required. The top or upper surface of the body 10has a central fore and aft channel or elongate depression 13 to receivethe powerplant described below. This elongate depression 13 extends fromthe aft end of the body 19 to a point some distance forwardly of thecentral vertical axis of the craft. As best seen in FIGURES 3 and 4 ofthe drawings, the walls of the depression 13 smoothly merge with or jointhe adjacent surfaces of the body 10 and a substantial region of thedepression aft of its forward extremity is flared to form the upperportions of what I will term the bell-mouth 14 of a generally verticaljet pump passage or tube 15. This tube extends downwardly from thedepression 13 to the underside of the body 10. As best illustrated inFIGURE 1 and FIG- URE 2, the belhmouth 14 of the jet pump tube 15 converges downwardly to a throat 16 and the walls of the tube graduallydiverge downwardly from this throat to the exit of the tube to the endthat the tube is substantially venturi shape. Since the bell-mouth 14 isspaced aft of the forward extremity of the elongate depression 13 thereis what may be termed a rounded shoulder 17 where the bell-mouth anddepression merge near the forward end of the depression.

The powerplant proper has an elongate tubular or hollow casing 18 whichmay be cylindrical for the major portion of its length. This casing 18defines or provides the above mentioned plenum chamber 20, carries theair inlet 22 and carries or includes the main propulsive nozzle 24.While the specific powerplant details do not form a part of thisinvention, the powerplant for creating the propulsive fluid flow throughand from casing 18 may be of the type explained and claimed in mycopending application Serial Number 539,606, filed October 10, 1955. Asillustrated in the drawings, the casing 18 is arranged longitudinally inthe above described depression 13 in the top of the craft body 10 tohave the air inlet 22 adjacent and slightly aft of the shoulder 17 whichis of gentle curvature, and to present the propulsive nozzle 24 at oraft of the pointed rear end of the body. Further, it will be observedthe casing 18 may preferably be substantially submerged or contained inthe depression 13 to the end that the exterior of its periphery isgenerally coincident with or tangent to continuations of the uppersurface arcs of the body 10, at least throughout a substantial portionof the length of the easing. In FIGURES 1 to 4 inclusive, it will beobserved that the central longitudinal axis of the depression 13 and thecentral fore and aft axis of the casing 18 are pitched or inclinedupwardly and forwardly with respect to the central fore and aft axis ofthe body 10. The purpose and advantages of this disposition of thepowerplant casing will be described later. Where the craft is equippedwith a single propulsive system the longitudinal axis of the casing '18preferably intersects the central vertical axis of the body 10 and thefore and aft location of the casing 18 is such that it bridges orextends across the upper end of the jet pump tube 15 and its bell-mouth14.

While it is contemplated that the powerplant casing 18 may be supportedor mounted in any selected or ap propriate manner, it will usually bepreferred to support the casing in spaced relationship with the walls ofthe depression 13 to mechanically and thermally isolate the powerplantfrom the body 10 so far as practically possible and to expedite airflowinto the jet pump tube 15 during vertical propulsion phases.Accordingly, I have shown two front engine mounts at diametricallyopposite sides of the casing 18 slightly aft of the jet pump tube 15.These mounts 25 are in the nature of pivotal outlet or jettingconditions.

connections supporting the powerplant on an axis normal to thelongitudinal axis of the casing 18. The engine mounting means furtherincludes a rear mount 26 at the aft end of the casing 18 adjacent thenozzle 24 and having slotted or lost motion engagement with the body 10to permit difierential thermal expansion and contraction of the casingand body. The mounts 25 and 26 support the casing 18 in the depression13 in a manner to leave a relatively narrow continuous space between theexternal surface of the casing and the wall of the depression 13 toallow a free movement of insulating and isolating air therebetween.

The above mentioned propulsive nozzle 24 is in the nature of arearwardly convergent tubular aft portion or extension of the casing 13.The nozzle 24 serves to discharge or spout a relatively low velocitylarge mass flow of relatively low temperature heated air and combustiongases from the plenum chamber 20 for the translational propulsion of thevehicle. As will be described below, the nozzle 24 is obstructed whenvertical propulsive thrust is desired or required so as to divert themajor portions of the propusive air and gas stream to the jet pump tube15. The plenum chamber casing 18 is provided with a plurality of jetpump nozzles 39 discharging into the bell-mouth 14 and upper end of thejet pump tube 15. These nozzles 30 are designed to discharge relativelyhigh temperature air and gas streams or jets at high jetting velocitiesto bring about an etficient jet pump eifect and thereby obtain asubstantial vertical thrust sufficient to propel the vehicle verticallyfor vertical or substantially vertical take-off and to sustain thevehicle for controlled slow vertical or substantially vertical landing.

As best illustrated in FIGURES 5, 6 and 8, there is a series of jet pumpnozzles 30 on the underside of the casing 18 directed downwardly andslightly to the rear in the downwardly convergent mouth of the jet pumptube 15. The plurality of relatively small jets issuing from the nozzles30 in the entrance of the jet pump tube greatly increase the air mixingshear area, thereby permitting the employment of a shorter jet pumptube, and jet boundary discontinuities are restrained to smalldistances. The shorter jet pump tube in turn provides reduced wallfriction losses and provides more uniform Furthermore, the numeroussmall nozzles 30 produce efiiux noise of relatively high frequency, orin the inaudible range, the former being muffled in the jet pump tube.Such noise as does escape is of high frequency, and therefore highlydirectional, which prevents noise from being spread over large areas.The angular direction of the nozzles 30 reduces the turning losses ofthe large volume or flow of ducted compressor air diverted to the jetpump tube 15, as will be apparent. The jet pump nozzles 30 themselvesprovide a multiplicity of spaced downwardly convergent jetting openings,each of which is equipped with a butterfly valve 31. The valves 31 arearried by shafts 32 to be movable in unison between closed positionswhere they close ofi? their respective nozzles 30, during translationalpropulsion of the vehicle, and open positions where they form throats inthe nozzles 31 to assist in bringing the fiow therethrough to thesupersonic regime. It can be provided, if desired, that one or morenozzles always remain open, to furnish some jet tube induced flow, forcontinuous boundary layer extraction during level flight. The valves 31are airfoil shape in cross section and when their airfoil configurationsare axially aligned with the passages through the nozzles 30 theyprovide the nozzles with effective throats of convergent-divergentconfiguration to assist in bringing about the supersonic flow justmentioned. Furthermore, the trailing downwardly convergent surfaces ofthe open butterfly valves present or form thrust surfaces in the jetpump nozzles themselves to impart or assume a vertical lift to thevehicle at the nozzles. The walls of the jet pump tube 15 may beperforated, as shown at 33, for acoustical silencing or damping, theperforations leading to closed cells 29 or chambers in the structure ofthe tube and, if desired, the rear portion of the plenum chamber or ofthe nozzle bulb may be perforated in a similar manner for the samepurpose. In this connection it may be observed that while the freevelocity of the air and gas stream at the throat of the jet pump tube ishigh, the relative velocity be tween the air and gas streams ismoderate, and the velocity at the exit of the tube is considerablyreduced, by intermediate recompression in the jet tube, thus lesseningthe sound or noise output externally. The detailed operation of the jetpump means of the open circuit including the suction or reduced pressureaction at the bellmouth 14 and adjacent regions,'will be more fullydescribed in connection with the overall operation of the propulsivesystem.

In order that the major portion, say 90%, of the powerplant air flow maybe diverted for discharge through the jet pump nozzles 30, I providemeans for closing or restricting the propulsive nozzle 24. An axiallymovable tubular bulb 114 is supported for movement between a positionforward and clear of the nozzle 24 and a closed position where itengages in and restricts the nozzle. The bulb 114 is supported on therear end of a rod 116 by a universal joint 115 and the rod enters acylinder 117. The cylinder 117, the muif 113, the aft manifold 82, andother adjacent equipment are supported on one or more hollow streamlinedstruts 118 on the casing 18. Flexible control elements in the form ofchains or cables 120, or the equivalent, extend through the struts 118,are guided over sprockets 121 and are secured to the interior of thehollow or tubular bulb 114 at angularly spaced points. The tubular bulb114 has a rearwardly convergent nozzle opening 122 which discharges areactive stream or jet of air under pressure. By differentiallyoperating the cables 120, the nozzle bulb 114 can be moved through aconical angle of 70 or more so that this jet of compressed air may beutilized to obtain a trimming action or pitch or turn control. It shouldbe observed that the substantially spherical bulb 114 is free to moveangularly in the main propulsive nozzle 24 also when the bulb is in itsclosed position essentially seated in the mouth of the main nozzle.

The nozzle bulb 114 is pressure balanced to facilitate its readyoperation without involving heavy tension in control connectionsthereto. The pressure balancing means includes the above mentionedcylinder 117 and a piston 124 on the rod 116 for operating in thecylinder.

A vent line 123 maintains the forward end of the cyl- 0 inder 117 incommunication with the atmosphere. A pressure line 125 communicates withthe aft end of the cylinder 117 and extends to a convenient source ofair pressure so as to impose super atmospheric pressure on the aft sideof the piston 123 and thus bias the nozzle bulb 114 toward its openposition. This facilitates movement of the bulb 114 from the closedposition to the open position. In practice, the line 125 may have itsouter end open to the plenum chamber 20 or other region of relativelycool fluid under pressure. Since flow conditions in the nozzle 24 tendto urge the bulb 114 to the closed position, there is no necessity tobias the bulb toward the closed position. An air scoop or blast tube 126is associated with the pressure balancing means just described to directrelatively cool plenum chamber air against the nozzle bulb actuating andbalancing mechanisms. The tube 126 discharges inwardly and rearwardlyagainst the cylinder 117, the chains 120, the sprockets 121, etc. toprevent this equipment from becoming excessively hot.

The gas flow at the nozzles 30 will total about 26 lbs. per second,producing a jet velocity of about 2300 ft. per second inasmuch as thegases discharge into a depressed region of the jet pump tube because theflow velocity of entrained air at the throat of the jet pump tube is ap-6 proximately sonic, or 1000 ft. per second. This, in turn, will producea jet net thrust of about 1700 lbs. with the temperature at 1520 F.Assuming the efliciency of the jet pump to be 40% the conditions in thevertical lift tube will be substantially as follows:

Total gas and air flow lbs. per second, a jet discharge velocity of 635ft. per second, a stream temperature of 400 F. and a thrust output of2,280 lbs. The recompression ratio between the throat and exit of thejet pump amounts to about 1.9 to 1.

Since the inducted air flow is in the ratio or amount of 3.5 times thejet nozzle flow the jet pump effects over 33% increase in lift. The bulb114 of the rear propulsive nozzle 24 may be directed at an angle of 60to the ground with the bulb in the closed position. The jet opening 122of the bulb 114, directed in this manner, discharges 10% of the ductedcompressor air flow at the same velocity and temperature as the rearmain propulsive nozzle to add 100 lbs. upward thrust, providing a totallifting force of 2,380 lbs.

The jet pump tube 15 is provided with one or more valves 128 adapted toclose or be closed during translational flight and capable of being setor directed for banking control during vertical flight. i[ have showntwo companion valves 128 of airfoil or streamlined cross section carriedby or fixed to fore and aft shafts 130. The valves 128 are preferablyunbalanced, that is their axes of pivotal movement are unequally spacedbetween their fore and aft or upper and lower edges so as toautomatically open when the air and gas flows downwardly through the jettube 15 and to automatically close during translational flight of thevehicle. A releasable or normally free control system is provided todirect the valves 128 for the purpose of banking control or trimmingduring vertical or substantially vertical flight. This control includescrossed cables operatively connected at one end with the valves 128. Thecables 160 have their other ends connected with lever horns 161 on amono manual lever 144.

The butterfly valves 31 of the jet pump nozzles 30 and the bulb 114 ofthe main propulsive nozzle 24 are preferably interconnected forsimultaneous control or operation. I have shown a suitable mechanicallinkage 143 between the shafts 32 of the butterfly valves and the chains120 of the nozzle. This linkage is operable by the manual lever 144between a position where the bulb 114 is forward or open and the valves31 are closed, and a second position where the bulb 114 is closed andthe valves 31 are open. The operative connection between the valveshafts 32 and the nozzle bulb 114 includes levers 162 on the valveshafts and a cable 163 connected with the levers and extending to apiston 164 operating in a cylinder 165. The above described cables orchains 120 connected with the interior of the nozzle bulb 114 operateover pulleys 166 on three equally spaced lever horns 161 on the manualcontrol lever 144, and also have their ends connected with the piston164. Air pressure lines 167 supply operating pressure to the oppositeends of the cylinder 165. A manual valve 168, preferably of thepush-button type, is operable to charge one end of the cylinder with airpressure to simultaneously pull the three cables 120 and thus move thenozzle bulb 114 to the open position. The cable 163 is pulledsimultaneously with the cables 120 to close the jet tube valves 32. Thisconditions the powerplant for level flight operations. Air pressuresupplied to the opposite ends of the cylinder 165 relaxes tension on thecables 120 and the bulb 114 moves to the closed position in the nozzleby air flow there through and tension on the cable 163 is simultaneouslyrelaxed so that pressure from the plenum chamber moves the valves 31 totheir open positions. This conditions the propulsive system for verticalor substantially vertical flight operations.

If desired, the above described unbalanced valves 128, adjacent the exitof the jet pump tube 15, may have semicircular cut-outs or openings 145opposite one or more of the jet nozzles of the plenum tube being leftopen; to discharge a limited stream of ducted compressor air forboundary layer air extraction from the airplanes upper surface duringlevel or translational flight when all other valves associated with thejet tube are closed, it being understood that these openings areoptional and may be omitted if desired. It is obvious that thebell-mouth of the jet tube may optionally be faired to the external airstream, if desired, by sliding sheets of metal, or the equivalent.

Assuming the aircraft to be on a field or take-off station, it may bedesired to operate the craft substantially vertically from the station.The propulsive system is conditioned for this action by simultaneouslyclosing the nozzle bulb 114 and opening the jet pump nozzles 39 in themanner described above. The manual lever 144 is operated to set thenozzle bulb 114- in a suitable trim position or may be operated to movethe bulb during vertical ascent, the lever 144 also being operable toset or adjust jet tube valves 123 for banking purposes. In thisconnection it should be noted that the 120 spacing of the horn levers161 provides for this differential or directional control of the bulb114 and valves 12%. With the jet pump tube 15 open and the jet pumpnozzles discharging downwardly into the tube, the air and combustiongases jetted from the nozzles mix with inducted outside air enteringthrough the bell-mouth 14 to create a strong negative pressure orsuction at the top of the fuselage 10. This negative pressure isincreased by the immediately adjacent air inlet 22 of the plenum chamber20, augmenting the vertical lift etfect of the jet pump. With the jetpump in operation substantially 90% of the ducted compressor air flow isdirected through the spaced jet pump nozzles 30 to produce a highlyefiicient jet pump action. Under a typical vertical ascent condition thegas flow through these nozzles will be about 26 pounds per second at avelocity of 2300 feet per second, producing a jet net thrust of 1700pounds. Assuming the efiiciency of the jet pump to be approximately thetotal gas and air flow through the vertical jet lift tube 15 will be 115pounds per second at an outlet jetting velocity of 635 feet per second,producing a thrust of 2,380 pounds. It should be noted that the valves31 in the jet pump nozzles form throats and the mixed air and combustiongas jets become supersonic as they pass the valve throat restriction andapproach the depression at the throat of the jet pump tube. Theplurality of relatively small jet nozzles bring about an increasedmixing shear area in the jet pump tube, allowing the tube to be maderelatively short with proportionately less wall friction loss and with amore uniform outlet condition.

When sufiicient altitude has been obtained the propulsion system may bereadily conditioned for translational flight by moving the lever 144 tosimultaneously open the propulsive nozzle bulb 1'14 and to close the jetpump nozzles 30. With the jet pump tube 15 closed, the entire mass flowof air flows aft through the plenum chamber, to discharge from thenozzle 24 as a propulsive jet.

For vertical or substantially vertical descent, the powerplant system isconditioned as above described for the vertical ascent so that the jetpump tube 15 acts to provide a substantial vertical lift augmented orassisted by the negative pressure condition in the bell-mouth region.

Having described only typical forms of the invention I do not Wish to belimited to the specific details herein set forth, but wish to reserve tomyself any variations or modifications that may appear to those skilledin the art and fall within the scope of the following claims.

I claim:

1. In an aircraft having a body the combination of; a plenum chamberextending fore and aft of the upper side of the aircraft body, a jetpump tube extending from the upper side of the body beneath said plenumchamber to the underside of the body, jet pump nozzle means dischargingfrom the chamber downwardly into the tube, a propulsive nozzle at theaft end of the chamber, means creating a flow through the chamber, andmeans controlling fiow through said jet nozzle means and said propulsivenozzle whereby said flow may be discharged either from said jet nozzlemeans to produce a jet pump effect through said tube or a propulsivedischarge jet through said propulsive nozzle.

2. In an aircraft having a body the combination of; a fore and aftchannel in the upper side of the body, a jet pump tube extendingdownwardly from the channel to the under side of the body, powerplantmeans in the channel comprising an elongate casing, and means in thecasing producing an aft directed stream of propulsive fluid, apropulsive nozzle at the aft end of the casing discharging said streamin the form of a propulsive jet, means for substantially closing thepropulsive nozzle, jet pump nozzles extending laterally from said casingfor discharging said propulsive fiuid downwardly into said tube whensaid propulsive nozzle is substantially closed, and means for closingthe jet pump nozzles when the propulsive nozzle is open.

3. In an aircraft having a body the combination of; a fore and aftchannel in the upper side of the body, a jet pump tube extendingdownwardly from the channel to the under side of the body, powerplantmeans in the channel comprising an elongate casing, a flaring upwardlyfacing bell-mouth entrance for the upper end of said tube where it joinsthe powerplant means in the channel, means in the casing producing anaft directed stream of propulsive fluid, a propulsive nozzle at the aftend of the casing discharging said stream in the form of a propulsivejet, means for substantially closing the propulsive nozzle, jet pumpnozzles extending laterally from said casing for discharging saidpropulsive fluid into said tube when said propulsive nozzle issubstantially closed, and means for closing the jet pump nozzles whenthe propulsive said nozzle is open.

4. In an aircraft having a body the combination of; a fore and aftchannel in the upper side of the body, a jet pump tube extendingdownwardly from the channel to the under side of the body, powerplantmeans in the channel comprising an elongate casing, and means in thecasing producing an aft directed stream of propulsive fluid, apropulsive nozzle at the aft end of the casing discharging said streamin the form of a propulsive jet, means for substantially closing thepropulsive nozzle, jet pump nozzles extending laterally from said casingfor discharging said propulsive fluid downwardly into said tube whensaid propulsive nozzle is substantially closed, valve means for closingthe jet pump nozzles, and means operable to open the valve means and toactuate the propulsive nozzle closing means to substantially close saidpropulsive nozzle so that said stream discharging through the jet pumpnozzles creates a jet pump action to produce a vertical lift, said valveoperating means further operable to close the valve means and to actuatethe propulsive nozzle closing means to open said propulsive nozzle sothat said stream discharges from the propulsive nozzle to produce aforward thrust.

5. In an aircraft the combination of; a fuselage having a duct extendingvertically therethrough, a bell-mouth atmospheric air entrance to theduct, and a powerplant including a casing carried by the fuselage tobridge the bell-mouth, means in the casing producing a stream ofpropulsive air, and at least one jet nozzle on the casing dischargingsaid stream through the bell-mouth into the duct.

6. In an aircraft the combination of; a fuselage having a duct extendingvertically therethrough, a bell-mouth atmospheric air entrance to theduct, a powerplant including a casing extending substantiallytransvcrsely across the bell-mouth, the casing having an air inlet inthe bell-mouth, said casing having a propulsive nozzle directedtransversely of the duct and having a jet nozzle directed into the ductfrom the hell-mouth, and means producing propulsive airflow through thecasing for discharge from said nozzles.

7. In an aircraft the combination of; a fuselage having a duct extendingtherethrough in one direction and a bell-mouth atmospheric air entranceto the duct, a surface channel extending from the hell-mouth in adirection generally transversely of the duct, a powerplant in thechannel having an air inlet in the bell-mouth and including jet pumpnozzle means discharging into the duct, and means producing a propulsivefluid flow for discharge from the nozzle means.

References Cited in the file of this patent UNITED STATES PATENTSKolerofi Dec. 21, 1920 Morize Apr. 19, 1921 Koleroif May 13, 1924Craddock May 18, 1926 Warner "June 29, 1948 Doak Jan. 10, 1956 BertinJan. 26, 1960 FOREIGN PATENTS France Jan. 15, 1945 Australia Nov. 24,1952

